Polishing apparatus

ABSTRACT

A polishing apparatus includes a cyclic mechanism moving cyclically in a certain direction, a holder moving cyclically by the cyclic mechanism in a direction parallel to an object to be polished, a plurality of polishing pins held on the holder, a magnet member including a first part which is exposed on a front face side of the polishing pin and a second part which is not exposed on the front face side of the polishing pin, a part of the second part being covered with a non-magnetic material, and a polishing member held on the polishing pin by magnetic force of the magnet member and polishing a tip of the object to be polished by the cyclic motion of the cyclic mechanism, wherein a contact area of the polishing member and the polishing pin includes a contact area of the magnet member and the polishing member.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is based upon and claims the benefit of priority of the prior Japanese Patent Application No. 2008-275809, filed on Oct. 27, 2008, the entire contents of which are incorporated herein by reference.

FIELD

The embodiments discussed herein are related to a polishing apparatus which polishes tips of pins.

BACKGROUND

Conventionally, electronic circuits that include semiconductor components, such as, integrated circuits (ICs), large scale integrations (LSIs) or the like, have been formed on a circuit board that is incorporated in an electronic apparatus. For such electronic circuits discussed above (especially, for semiconductor circuits), operation tests for checking whether the electronic circuits operates normally or not are performed by using a circuit board testing apparatus before the electronic circuits are incorporated in the electronic apparatus. Typically, connectors are attached to an end of the circuit board when undergoing operation testing performed by such circuit board testing apparatus.

Japanese Laid-Open Patent Publication No. 58-169068 discusses a method of applying vibration and thereby removing oxide films formed on surfaces of pin-shaped connection terminals (electrode), such as connector pins or the like to achieve contact with low resistance.

According to the method discussed in Japanese Laid-Open Patent Publication No. 58-169068, probes come in contact with electrodes on the circuit that undergoes the test while supersonic vibration or the like is applied from a rear side of the circuit board. This allows micro-displacement to occur by the vibration at contact portions of the probes, so that the oxide films formed on the surfaces may be removed.

As other conventional techniques, Japanese Laid-Open Patent Publication No. 2005-131774 and Japanese Laid-Open Patent Publication No. 2000-84848 are discussed. In the former, a structure that facilitates attaching and detaching of a grinding blade is discussed. In the latter, a structure for attaching a magnet(s) provided on a grinding unit is discussed.

SUMMARY

According to an aspect of the described embodiments, a polishing apparatus includes a cyclic mechanism moving cyclically in a certain direction, a holder moving cyclically by the cyclic mechanism in a direction parallel to an object to be polished, a plurality of polishing pins held on the holder, a magnet member including a first part which is exposed on a front face side of the polishing pin and a second part which is not exposed on the front face side of the polishing pin, a part of the second part being covered with a non-magnetic material, and a polishing member held on the polishing pin by magnetic force of the magnet member and polishing a tip of the object to be polished by the cyclic motion of the cyclic mechanism, wherein a contact area of the polishing member and the polishing pin includes a contact area of the magnet member and the polishing member.

The object and advantages of the invention will be realized and attained by means of the elements and combinations particularly pointed out in the claims.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are not restrictive of the invention, as claimed.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 illustrates a side view indicative of an entire structure of a polishing apparatus according to a first embodiment;

FIG. 2 illustrates a plane view indicative of the entire structure of the polishing apparatus according to the first embodiment;

FIG. 3 illustrates a view indicative of an appearance of a male connector;

FIG. 4 illustrates a view indicative of a holder which holds polishing pins;

FIG. 5A illustrates a partial sectional view indicative of a state where the polishing pins are attached to the holder and FIG. 5B illustrates another view indicative of the state where the polishing pins are attached to the holder;

FIG. 6 illustrates an enlarged sectional view indicative of an internal structure of the polishing pin;

FIG. 7 illustrates an enlarged sectional view explaining a magnetic circuit of the polishing pin;

FIG. 8 illustrates a flow chart explaining manufacturing processes of the polishing pin;

FIGS. 9A through 9D illustrate views sequentially explaining the manufacturing processes of the polishing pin;

FIG. 10 illustrates an enlarged sectional view indicative of an internal structure of a polishing pin according to a second embodiment;

FIG. 11 illustrates a view explaining an operation test by a circuit board testing apparatus;

FIG. 12A illustrates an enlarged sectional view indicative of a conventional male connector and a conventional female connector before the both connectors are coupled to one another and FIG. 12B illustrates an enlarged sectional view indicative of the conventional male connector and the conventional female connector after the connectors are coupled to one another; and

FIG. 13A illustrates an enlarged sectional view indicative of another conventional male connector and another conventional female connector before the both connectors are coupled to one another and FIG. 13B illustrates an enlarged sectional view indicative of another conventional male connector and another conventional female connector after the both connectors are coupled to one another.

DESCRIPTION OF EMBODIMENTS

As illustrated in FIG. 11, a circuit board testing apparatus P includes a cable 1 and a female connector 2. The female connector 2 is coupled to an end of the cable 1, and the other end of the cable 1 is connected to the circuit board testing apparatus P. A circuit board 5, which undergoes an operation test, includes an electronic component(s) 6 disposed on the circuit board 5 and a male connector 7 for testing an operation of the circuit board 5.

In performing the operation test of the circuit board 5, which undergoes the operation test, by using the circuit board testing apparatus P, the operation test is performed by electrically connecting the female connector 2, which is coupled to the cable 1 of the circuit board testing apparatus P, with the male connector 7 disposed on the circuit board 5.

As illustrated in FIG. 12A, the male connector 7 includes connector pins 9, which are a plurality of connection terminals disposed inside a housing 8 (see 2 pins in FIG. 12A). One ends of these connector pins 9 are connected, as lead terminals 9 a (see FIG. 11), to the circuit board 5. The connector pins 9, disposed inside the housing 8 of the male connector 7, have tips each having a sharp-spearhead shape.

On the other hand, as illustrated in FIG. 12A, the female connector 2 includes receptacles 4 (electrode) in the housing 3 thereof. Each of the receptacles 4 are formed in a bifurcated shape and electrically connected with each of the connector pins 9 of the male connector 7 in a state such that each of the receptacles 4 is coupled to each of the connector pins 9.

As illustrated in FIG. 12B, when each of the connector pins 9 is inserted into each of the receptacles 4, which are formed in a bifurcated shape, in the female connector 2, each of the connector pins 9 and each of the receptacles 4 are joined together and both are rubbed against each other. Because of this, the female connector 2 is electrically connected with the male connector 7.

If a large number of the circuit boards 5, which undergo the test, are tested, it is desirable that the female connectors 2 have durability. The individual circuit board 5, which is an object of the test, undergoes the test only once. On the other hand, the receptacles 4 of the female connector 2 are used for many male connectors 7 in every single case. Consequently, the receptacles 4 (electrode) facing the connector pins 9 are scraped off by abrasion. As a result, a gap in each receptacle 4 is widened, and this may cause bad electrical contact.

The bad electrical contact between the receptacles 4 and the connector pins 9 of the male connector 7 disclosed above are suppressed (or reduced) by employing a connector structure in which spring probes are used for the female connector 2.

As illustrated in FIG. 13A, a housing 3 a of a female connector 2 a includes spring probes 4 a. Each of the spring probes 4 a further includes a crown member 4 b, a tip of which is equipped with a plurality of projections, and a deformation member 4 c which is deformed in a lateral direction by pressing force.

As illustrated in FIG. 13B, when the female connector 2 a is engaged with the male connector 7, the crown members 4 b of the spring probes 4 a are pressed in a depth direction (in a direction indicated by a dotted line arrow in FIG. 13B) in response to each tip of the connector pins 9 of the male connector 7 coming in contact with each of the crown members 4 b, so that each of the deformation unit 4 c is compressed and deformed with the pressing force. Herewith, abrasion of the electrodes 4, which is caused by joint members of the female connector 2 a and the connector pins 9 of the male connector 7, is suppressed or reduced.

In the above-disclosed connector structure in which the spring probes are used, each tip of the connector pins 9 of the male connector 7 comes in contact with the each of the crown members 4 b of the female connector 2 a.

Due to this, oxide films may be formed on surfaces of the tips of the connector pins 9 due to temperatures in performing a process, such as, reflow soldering after implementation of the male connector 7 on the circuit board 5 and due to an environment where the circuit board 5 is placed, such as, a period between the implementation of the male connector 7 and the operation test.

More specifically, a part except the tips of the connector pins 9 of the male connector 7 is configured to have low contact resistance with metal plating (for example, Sn, Ni, Au, or the like). However, since the tips of the connector pins 9 are not metal-plated, Cu which is a base material of the connector pins 9 is exposed. Since the oxide film is an insulation material, bad electrical contact between the crown members 4 b in the female connector 2 a and the tips of the connector pins 9 may be caused due to the oxide film.

More specifically, measurement may be performed without any problem in measuring voltage by engaging the female connector 2 a with the male connector 7, even if resistance is induced in a case where the female connectors 2 a equipped with the spring probes 4 a are used. However, when current is induced through the electronic component(s) 6 disposed on the circuit board 5 via the male connector 7 by using the female connector 2 a to perform measurement, a voltage drop occurs due to the contact resistance of the spring probes 4 a and due to the flowing current.

First Embodiment

In a first embodiment, roughly speaking as illustrated in FIG. 6, an engaging hole 50 for securely engaging an outer circumferential surface and a rear face portion of a magnet 42 is formed substantially at the center of a head member 32 that forms a polishing pin 30. An inner surface of the engaging hole 50 is covered with a non-magnetic material 41 while the magnet 42 is engaged with the polishing pin 30 in a state such that a surface of the magnet 42 is exposed. A polishing member 31 (file) having an outer diameter larger than an outer diameter of the magnet 42 is held on the polishing pin 30 by magnetic force of the magnet 42. Consequently, the polishing member 31 may be securely held and replaced with ease.

As illustrated in FIGS. 1 through 4, a polishing apparatus 10 includes a base board 11 entirely formed in a quadrangle shape, a motor attached board 12 provided substantially at a right angle relative to a part of the base board 11, a drive motor 13, a holder 20 for holding the polishing pin 30 that is provided with the polishing member 31 (herein after referred to as a “holder 20”), an air supplier 22, a dust collector 24, and a controller 25, in the first embodiment.

As illustrated in FIGS. 1 through 4, the motor attached board 12 is provided in a projecting manner on one end (on the left side in FIGS. 1 and 2) of the base board 11 and the drive motor 13 is attached on the motor attached board 12. A cam 15 is attached to an end of a rotation shaft 14 of the drive motor 13 and the cam 15 is engaged with a pin 19. The pin 19 will be disclosed below. In addition, a pair of an upper cover 16 a and a lower cover 16 b supporting the rotation shaft 14 of the drive motor 13 is fixedly disposed on the motor attached board 12.

Between the upper cover 16 a and the lower cover 16 b, the holder 20 is disposed. The holder 20 is supported by a pair of spring plates 17 (see FIG. 2) from both sides thereof and capable of moving cyclically in a space between the upper cover 16 a and the lower cover 16 b. The holder 20 is capable of holding the polishing pins 30 which is provided with the polishing members 31.

Here a certain gap is provided between the holder 20 and the upper cover 16 a and between the holder 20 and the lower cover 16 b. A pin attached board 18 is fixed on a surface of an end surface of the holder 20, the end surface being on a side closer to the drive motor 13. The pin 19 disposed on the pin attached board 18 in a projecting manner is engaged with the cam 15 provided at the end of the rotation shaft 14 of the drive motor 13.

The cam 15, which is attached to the rotation shaft 14 of the drive motor 13, and the pin 19 are configured to form an eccentric coupling 15 a. More specifically, when the cam 15 rotates in a certain direction (in the direction indicated by an arrow R in FIG. 2) by the drive motor 13 by virtue of the eccentric coupling 15 a, the pin 19 engaged with the cam 15, the pin attached board 18, and the holder 20 integrally performs a cyclic motion in certain directions (in the directions indicated by arrows S in FIG. 2) in an integrated manner.

The holder 20, which is supported by the spring plates 17, performs a cyclic motion in the certain directions (in the directions indicated by the arrows S in FIG. 2) by virtue of rotations of the drive motor 13. As disclosed below, the connector pins 9 may be polished by the polishing members 31 provided at the tips of the polishing pins 30 with the cyclic motion. Note that the cyclic motion of the holder 20 may be replaced with other cyclic motions. As one example of the cyclic motions, a rotating motion may be possible.

Moreover the air supplier 22 fixedly disposed on an upper surface of the base board 11 is an apparatus that supplies an air purge tube 23 with high pressure air and is capable of blowing away dust scraped off when the polishing members 31 attached to the polishing pins 30 polishes the tips of the connector pins 9.

Furthermore the dust collector 24, fixedly disposed on the upper surface of the base board 11 in a similar manner, has a dust collection tube 24 a which faces toward the polishing pins 30. The dust generated in polishing the tips of the connector pins 9 by using the polishing members 31 is absorbed with the dust collection tube 24 a to reduce, if not prevent, the dust remaining inside of the housing 8 of the male connector 7.

In addition, the controller 25 fixedly disposed on the upper surface of the base board 11 in a similar manner includes functions of not only controlling air supply by the air supplier 22 and dust collection by the dust collector 24 but also controlling rotation of the drive motor 13 and controlling positions by a shifting mechanism 21.

On the other hand, the shifting mechanism 21 is disposed on the other end of the base board 11 (on the right side in FIGS. 1 and 2). As illustrated in FIGS. 1 and 2, the shifting mechanism 21 includes a base platform 21 a and a pair of wheels 21 b. The base platform 21 a further includes the circuit board 5 on which there are provided the male connector 7 (that is, the housing 8 with a rear cover 8 a) equipped with the plurality of connector pins 9 (that is, the objects of the test disclosed above) and the electronic component(s) 6 that includes semiconductor components, such as, ICs and LSIs. The pair of wheels 21 b moves the base platform 21 a in a certain direction (in the left direction in FIGS. 1 and 2).

As illustrated in FIGS. 1 through 3, the plurality of connector pins 9 (see FIG. 3) in the male connector 7 fixedly disposed on the circuit board 5 mounted on the base platform 21 a is further mounted on an upper part of the base platform 21 a in a manner that the connector pins 9 faces the holder 20 (on the left side in FIGS. 1 and 2).

Moreover when the male connector 7 moves toward and approximates the polishing apparatus 10 by the shifting mechanism 21, the tips of the polishing pins 30 are placed at positions where the tips of the connector pins 9 of the male connector 7 face the tips of the polishing pins 30, on a side of the polishing apparatus 10. The number of polishing pins 30 corresponds to the number of connector pins 9, and these polishing pins 30 are attached inside of pin reception holes 26 (see FIG. 5A) formed in the holder 20 disclosed above.

Here the holder 20 performs the cyclic motion in the certain directions (S directions) with the rotation of the drive motor 13, and since the tips of the polishing pins 30 face the tips of the connector pins 9 of the male connector 7 regardless of local positions in response to the cyclic motion of the holder 20, the tips of the polishing pins 30 may come in contact with the tips of the connector pins 9 upon termination of the motion of the male connector 7. Thus, tips of the connector pins 9 may be polished by the polishing members 31.

The plurality of polishing pins 30 (see FIGS. 5A and 5B) is provided relative to the holder 20, and the tips of the connector pins 9 provided on the male connector 7 may be polished by the polishing members 31 provided on the polishing pins 30, in the polishing apparatus 10 disclosed above.

As illustrated in FIGS. 5A and 5B, an outer diameter of a neck member 33, which is coupled to the head member 32 of the polishing pin 30, is formed smaller than an outer diameter of the head member 32 or an outer diameter of a body member 34. In addition, the body members 34 are received in the pin reception holes 26 formed on the holder 20, and elastic springs 36 are inserted and fixed between one end of the each body member 34 and a deep end of the each pin reception hole 26.

Furthermore, pin retaining plates 35 are fixed at each of openings 26 a of the pin reception holes 26 in a state such that each of the neck members 33 of the polishing pins 30 is supported from both sides thereof by the pin retaining plates 35. The neck members 33 and the head members 32, at the tips of which the polishing members 32 are held by magnetic force, are projected outside of the holder 20, and the body members 34 are received in the pin reception holes 26 of the holder 20 in a state such that elastic force of the elastic springs 36 is applied to the body members 34. The elastic springs 36 have a function of pressing the polishing members 31 onto tips of an object (connector pins 9), which undergoes the polishing, by the elastic force of the elastic springs 36.

In response to the polishing pins 30, configured as disclosed above, coming in contact with the tips of the connector pins 9 and the polishing pins 30 (polishing members 31) being pressed in a certain direction (in a Z direction in FIG. 5A), the body members 34 elastically compress the elastic springs 36 and sinks into the polishing holders 20. The plurality of tips of the connector pins 9 having different heights is effectively polished, while corresponding to the heights of the respective connector pins 9. Moreover, the degree of how much the polishing pins 30 sink into the holder 20 is adjusted with the length of each neck member 33.

The first embodiment has a structure in which a small magnet 42 (the outer diameter thereof is approximately 1 mm) is used individually for each polishing pin 30 corresponding to each individual connector pin 9 provided in the housing 8 of the male connector 7. With the structure disclosed above, a leakage magnetic field that leaks from around the magnet 42 may be reduced. Thus the polishing apparatus 10 is preferable for testing the test objects, for example, a magnetic element or the like, which is susceptible to an external magnetic field.

On the other hand, if a large magnet is used, a leakage magnetic field that leaks from around such magnet becomes greater, and the leakage magnetic field causes an adverse effect on the magnetic element or the like.

[Structure of Polishing Pin]

Hereinafter, an entire structure of the polishing pin 30 will be disclosed in detail with reference to FIGS. 6 and 7. FIG. 6 illustrates an enlarged sectional view indicative of an internal structure of the polishing pin. FIG. 7 illustrates a view for explaining a magnetic circuit of the polishing pin.

As illustrated in FIG. 6, an entire shape of the polishing pin 30 is formed in a long cylindrical shape. The polishing pin 30 includes the head member 32, the neck member 33, and the body member 34. Moreover, the polishing member 31 for polishing the tip of the connector pin 9 is held at the tip of the head member 32 by magnetic force of the magnet 42.

In actually replacing the polishing member 31 attached to the polishing pin 30, a replacement operation is performed by approximating a magnet, which has stronger magnetic force than the magnetic force of the magnet 42 provided in the polishing pin 30, from a side of a polishing surface (on the right side in FIG. 6) of the polish material 31, so that the polishing member 31 may be detached from the polishing pin 30. Moreover, the magnet 42 may be detached by directly pinching the magnet 42 with fingers.

Note that the actual polishing member 31 is a file member and both surfaces thereof are file-like surfaces (rough, uneven or scabrous surfaces). So a polishing member, having a surface on which a grinding process is performed, is used.

In addition, the engaging hole 50 capable of engaging with an outer circumferential surface of the magnet 42 is formed substantially at the center of the head member 32 of the polishing pin 30, and the non-magnetic material 41, which forms the magnetic circuit around the magnet 42, the polishing member 31, and the polishing pin 30, is provided between an inner circumferential surface of the engaging hole 50 and the outer circumferential surface of the magnet 42.

As the head member 32 (magnetic material) forming the polishing pin 30, for example, an iron+nickel plating (rust-resistant plating) or stainless steel (mainly, the model number in the four hundreds of Steel Use Stainless [SUS]) may be used. In addition, for example, epoxy resins, adhesives, and cylindrical resin pipes made of resin (sleeve members) may be used as the non-magnetic material 41 interposed between the engaging hole 50 of the polishing pin 30 and the magnet 42. Note, however, that it is not always necessarily to interpose the non-magnetic materials between the engaging hole 50 and the magnet 42. It may also be possible to provide a space (gap) or a clearance between the engaging hole 50 and the magnet 42.

Moreover, for example, a neodymium magnet, a samarium-cobalt magnet, a ferrite magnet or the like may be used as the magnet 42. Furthermore, as the polishing member 31, magnetic materials are used for magnetically attaching the polishing member 31 to the magnet 42, and for example, a carbon tool steel or the like may be used.

As illustrated in FIG. 6, roughly speaking, the outer diameter of the polishing member 31 is set to a certain outer diameter T₁ (T₁ is approximately equal to 2 mm) because a pitch of the connector pin 9 arranged inside the male connector 7 is approximately 2.5 mm. In addition, the length of the magnet 42 is set to a certain length T₂ (T₂ is approximately equal to 10 mm). The outer diameter of the magnet 42 is set to a certain diameter T₃ (T3 is approximately equal to 1 mm).

As illustrated in FIG. 6, the engaging hole 50 provided in the polishing pin 30 has a step-formed portion 51, a hole 52, a tapered potion 53, and a hole 54. The step-formed portion 51 is formed such that a dimension of the step-formed portion 51 is substantially equal to an outer circumferential surface of the polishing pin 30. The hole 52 is formed such that a dimension of the hole 52 is smaller than that of the step portion 51. The hole 54 is formed such that a dimension of the hole 54 is smaller than that of the hole 52. The tapered potion 53 is formed such that the potion 52 and the hole 54 are connected in a tapered manner. Hereinafter disclosed, the polishing member 31 is placed in the step-formed portion 51 of the engaging hole 50 formed in the polishing pin 30.

The polishing member 31 is placed in the step-formed portion 51 of the engaging hole 50 formed around a circumference (collar portion 37) of a tip of the head member 32 (on the right side in FIG. 6) of the polishing pin 30. Although the polishing member 31 may move slightly upward and downward (upward and downward directions in FIG. 6) due to the operation of the polishing apparatus 10, this motion may be suppressed by the collar portion 37 formed at the circumference of the polishing member 31.

In the first embodiment, when it comes to the magnet 42, in terms of a degree of engagement between the head member 32, which forms the polishing pin 30, and the magnet 42, the outer diameter of the magnet 42 is set to a certain set value (the set value is approximately equal to +0.05). More specifically, if the outer diameter of the magnet 42 is, for example, (φ1.0, a pore diameter of the head member 32 is a certain value (φ1.05±0.01). Since a shape of the engaging hole 50 formed in the head member 32 of the polishing pin 30 is formed as a tapered shape, the magnet 42 may be held in the head member 32 of the polishing pin 30 without a central axis of the magnet 42 being displaced when engaging the magnet 42 therein.

In addition, as illustrated in FIG. 7, the magnetic circuit is formed by magnetic field lines around the head member 32, the polishing member 31, and the magnet 42 that form the polishing pin 30, by providing the non-magnetic material 41 around the magnet 42. This magnetic circuit not only allows the polishing member 31 to be held on a front face of the polishing pin 30 even if the magnet 42 that is small but also allows the small magnet 42 to be detached therefrom with ease. Moreover, in the above case, it is possible to reduce, if not prevent, the leakage of magnetism leaking from around the magnet 42.

[Processes in Manufacturing the Polishing Pin 30]

Hereinafter, details of the manufacturing method of the polishing pin 30 according to the first embodiment are disclosed with reference to FIG. 8 and FIGS. 9A through 9D. FIG. 8 illustrates a flow chart explaining manufacturing processes of the polishing pin 30. FIGS. 9A through 9D illustrate views explaining the manufacturing processes of the polishing pin 30.

As illustrated in the flow chart in FIG. 8, first, a process of forming an engaging hole is performed (operation S1) where the engaging hole 50 (spot-facing hole) has the step-formed portion 51 substantially at the center of the head member 32 of the polishing pin 30 (FIG. 9A). More specifically, as illustrated in FIG. 9A, a through hole having a relatively large diameter is formed at an upper part of the engaging hole 50. As disclosed above, the step-formed portion 51 formed on the engaging hole 50 serves as a portion in which the polishing member 31 is placed.

Next a process of engaging a magnet is performed (operation S2) where the magnet 42 is engaged with an inside of the engaging hole 50 formed in the head member 32 of the polishing pin 30. Note that the engaging hole 50 is formed in operation S1. More specifically, as illustrated in FIG. 9B, the magnet 42 is engaged substantially at the center of the engaging hole 50. As disclosed above, when the magnet 42 is engaged with the inside of the engaging hole 50 of the head member 32, the engaging hole 50 of the head member 32 of the polishing pin 30 and the magnet 42 are held by the magnetic force.

Then a process of placing a non-magnetic member is performed (operation S3) where the non-magnetic material 41 is placed around a circumference of the magnet 42, and positions of the magnet 42 and the non-magnetic material 41 are fixed. As disclosed above, the non-magnetic material 41 used here is materials without having any magnetic characteristic, for example, a sleeve, a tube, an adhesive or the like, made of non-magnetic materials. In other words, the non-magnetic member 41 disclosed above allows a magnetic gap to be formed.

Here when the adhesive is used instead of the non-magnetic material 41, it may be avoided that the adhesive attaches and/or penetrates to a front face of the magnet 42 (the upper side in FIG. 9C) and a rear face of the polishing member 31 (the lower side in FIG. 9D). More specifically, a certain clearance t is secured as illustrated in FIGS. 9C and 9D, in the first embodiment.

Finally a process of holding a polishing member is performed (operation S4) where the polishing member 31 is magnetically held at the tip of the polishing pin 30. More specifically the polishing member 31 is placed inside of the engaging hole 50 formed in the head member 32 of the polishing pin 30.

As disclosed above, as illustrated in FIGS. 9A through 9D, the magnetic circuit may be formed around the head member 32, the polishing member 31, and the magnet 42 by providing the non-magnetic member 42 around the magnet 42. This not only allows the polishing member 31 to be held even if the magnet 42 is small but also allows the polishing member 31 to be detached there from with ease. Consequently, leakage of magnetism leaking from around the magnet 42 may be effectively reduced, if not prevented.

Moreover, since the small magnet is used as the magnet 42 provided in the polishing pin 30, the magnetic field lines formed by the magnet are confined within the magnetic circuit formed by the polishing member 31, the magnet 42, and the head member 32, so that the leakage of the magnetic field to an outside may be effectively reduced.

As disclosed above, in the polishing pin 30 of the polishing apparatus 10 according to the first embodiment, the magnet 42 is fixed to the inside of the engaging hole 50 in a state such that the non-magnetic material 41 is interposed inside the polishing pin 30, and the polishing pin 30 allows the polishing member 31 to be held on the front face of the polishing pin 30 by the magnetic force of the magnetic circuit formed around the polishing pin 30, the polishing member 31, the non-magnetic material 41, and the magnet 42. Consequently, the polishing member 31 may be held and replaced with ease. Thus only polishing members may be replaced with ease even when replacing the polishing members, provided on the polishing pins, are desirable. As a result, not only an interruption period of the polishing apparatus may be reduced, if not minimized, but also reduction in time for replacement and/or reduction in costs may be achieved.

Second Embodiment

Hereinafter a characteristic and a structure of a polishing pin 30 a according to a second embodiment will be disclosed. FIG. 10 illustrates an enlarged sectional view indicative of a structure of the polishing pin 30 a provided on the polishing apparatus 10 according to the second embodiment.

The first embodiment disclosed above has the structure in which the engaging hole 50 (step-formed portion 51) is formed at the tip of the head member 32 of the polishing pin 30 and the polishing member 31 is arranged inside of the step-formed portion 51. The second embodiment has a structure in which a polishing member 31 is directly held on a plane portion at an end of a head member 32 a.

As illustrated in FIG. 10, a tip of the head member 32 a forming the polishing pin 30 a has the plane portion, and the polishing member 31 is held by the magnetic force (a magnetic circuit formed by the polishing member 31, a magnet 42, and the head member 32 a) on the tip (on the right side in FIG. 10) of the magnet 42 a part of which is exposed on an engaging hole 50 a formed on the head member 32 a.

As disclosed above, in the polishing apparatus 10 according to the second embodiment, a structure is employed in which the polishing member 31 is directly held by the magnetic force on the plane portion of the head member 32 a forming the polishing pin 30 a. Since the process of forming the step-formed portion 51 (see FIG. 6), which is different from the engaging hole 50 for engaging the magnet 42 with an inside of the polishing pin 30 a prepared for the polishing apparatus 10, is unnecessary, manufacturing processes of the polishing pin 30 a may be facilitated.

Another Embodiment

The polishing member 31 is the file-like magnetic material in the first and the second embodiments disclosed above. It may also be possible to adhere or attached a non-magnetic polishing material (for example, alumina powders or the like) on a surface of a magnetic material, instead of the polishing member 31, so that the non-magnetic materials may be used as a polishing member for the polishing apparatus that polishes the connector pins.

Moreover it may also be possible to achieve a structure in which concave portions are formed inside a polishing member whereas convex portions are formed on a magnet provided on a polishing pin, and the convex portions of the magnet and the concave portions of the polishing member are engaged with each other by use of the convex portions and the concaved portions. In the above case, it is possible not only to securely hold the polishing member but also to reduce, if not prevent, motions in an axial direction.

All examples and conditional language recited herein are intended for pedagogical purposes to aid the reader in understanding the principles of the invention and the concepts contributed by the inventor to furthering the art, and are to be construed as being without limitation to such specifically recited examples and conditions, nor does the organization of such examples in the specification relate to a showing of the superiority and inferiority of the invention. Although the embodiment(s) of the present invention(s) has (have) been described in detail, it should be understood that various changes, substitutions, and alterations could be made hereto without departing from the spirit and scope of the invention. 

1. A polishing apparatus comprising: a cyclic mechanism moving cyclically in a certain direction; a holder moving cyclically by the cyclic mechanism; a plurality of polishing pins held on the holder; a magnet member including a first part which is exposed on a front face side of a polishing pin of said plurality of polishing pins and a second part which is not exposed on the front face side of the polishing pin, a part of the second part being covered with a non-magnetic material; and a polishing member held on the polishing pin by magnetic force of the magnet member, wherein a contact area of the polishing member and the polishing pin includes a contact area of the magnet member and the polishing member.
 2. The polishing apparatus according to claim 1, wherein the polishing pin includes an engaging hole with which a portion of the magnet member is engaged.
 3. A polishing apparatus comprising: a cyclic mechanism moving cyclically in a certain direction; a holder moving cyclically by the cyclic mechanism; a plurality of polishing pins held on the holder; a magnet member including a part exposed on a front face side of a polishing pin of said plurality of polishing pins; and a polishing member held on the polishing pin by magnetic force of the magnet member, wherein, in the polishing pin, an engaging hole, with which a portion of the magnet member is engaged, is formed and a non-magnetic member, which forms a magnetic circuit around the magnetic member, the polishing member, and the polishing pin, is provided between an internal circumferential surface of the engaging hole and an outer circumferential surface of the magnet member.
 4. The polishing apparatus according to claim 3, wherein the non-magnetic member comprises a sleeve member provided between the internal circumferential surface of the engaging hole and the outer circumferential surface of the magnet.
 5. The polishing apparatus according to claim 3, wherein the non-magnetic member comprises a hardening adhesive which is filled between the internal circumferential surface of the engaging hole and the outer circumferential surface of the magnet member.
 6. The polishing apparatus according to claim 3, wherein said non-magnetic member comprises a gap forming the magnetic circuit around the magnet member, the polishing member, and the polishing pin and is formed between the internal circumferential surface of the engaging hole and the outer circumferential surface of the magnet member.
 7. The polishing apparatus according to claim 1, further comprising: a suppressing member of the polishing pin which suppresses the polishing member from moving in the cyclic direction.
 8. The polishing apparatus according to claim 1, further comprising: an elastic member provided in a direction of the cyclic motion of the polishing pin and capable of moving the polishing pin relative to the holder by elastic force.
 9. A polishing apparatus comprising: a cyclic mechanism moving cyclically in a certain direction; a holder moving cyclically by the cyclic mechanism in a direction parallel to an object to be polished; a plurality of polishing pins held on the holder; a magnet member including a part exposed on a front face side of a polishing pin of said plurality of polishing pins; a polishing member held on the polishing pin by magnetic force of the magnetic member; an engaging hole which is provided substantially at a center of a head member forming the polishing pin and fixes the magnet member in an engaging manner; and a non-magnetic material which is provided between an inner circumferential surface of the engaging hole and an outer circumferential surface of the magnet member and forming a magnetic circuit around the magnet member, the polishing member, and the polishing pin, wherein the magnet member engages the polishing member with the polishing pin.
 10. The polishing apparatus according to claim 9, wherein a dimension of a front face of the magnet member exposed on a part of the polishing pin is smaller than a dimension of a rear face of the polishing member. 